\begin{table}[htbp]\centering
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\caption{Utilization index non-standardized -- Subcomponents}
\begin{tabular}{l*{4}{c}}
\toprule
                    &\multicolumn{1}{c}{(1)}&\multicolumn{1}{c}{(2)}&\multicolumn{1}{c}{(3)}&\multicolumn{1}{c}{(4)}\\
                    &\multicolumn{1}{c}{\textbf{\begin{tabular}[c]{@{}c@{}}Utilization\\index\end{tabular}}}&\multicolumn{1}{c}{\begin{tabular}[c]{@{}c@{}}Vaccination rates,\\children\textless 36 months\end{tabular}}&\multicolumn{1}{c}{\begin{tabular}[c]{@{}c@{}}\% of visits to HC,\\vs. other providers\end{tabular}}&\multicolumn{1}{c}{\begin{tabular}[c]{@{}c@{}}Number of visits\\ to HC\end{tabular}}\\
\midrule
Full treatment      &       0.027   &       0.022   &       0.007   &      -0.008   \\
                    &     (0.022)   &     (0.014)   &     (0.007)   &     (0.342)   \\
Constant            &      -0.020   &       0.739***&       0.231***&       9.128***\\
                    &     (0.016)   &     (0.017)   &     (0.007)   &     (0.316)   \\
\midrule
N                   &       7,288   &       4,212   &       7,288   &       7,288   \\
R$^{2}$             &       0.230   &       0.057   &       0.178   &       0.284   \\
Mean control group endline&      -0.013   &       0.787   &       0.326   &      15.327   \\
Mean control group baseline&      -0.008   &       0.755   &       0.377   &      14.186   \\
\bottomrule
\end{tabular}
\end{table}
